The correct response is:
The slope is positive because the line increases as you move from left to right on the graph.
In the scenario described, the line passes through the points (0, 0) and (6, 6). As you move from the left (0) to the right (6) on the x-axis, the corresponding y-values also increase (from 0 to 6). This indicates that the slope of the line is positive, as positive slopes represent an increase in y-values as x-values increase.